Postural drainage and chest percussion are used to clear chest congestion, states WebMD. These techniques help loosen and remove mucus from the lungs and are particularly helpful for people with a spinal cord injury, cystic fibrosis or other conditions causing difficulty for mucus to drain from the lungs.
Postural drainage involves performing specific poses that are designed to help drain different lobes of the lungs, according to WebMD. Gravity moves the mucus into the mouth, where it can then be spit or coughed out. Chest physiotherapy, or chest percussion, is performed by creating vibrations in the lungs to help move mucus from smaller airways to larger airways, where it can then be spit or coughed out. This is performed by patting a cupped hand on the chest to vibrate the airways of the lungs.